There’s an argument to be made that the Bregenz Festival’s floating shows on the waters of Lake Constance are not really opera but a mix of performance and installation art. But let’s not go there. If amped-up acoustics along with jaw-dropping sur- or hyperrealistic spectacle in the great outdoors aren’t for you, just opt out. The farewell reprise of last summer’s visually intoxicating, emotionally seismic Madama Butterfly is the attraction this year. Between Michael Levine’s décor and Andreas Homoki’s direction, it hits hard. It its way, it honors Puccini, too. —Matthew Gurewitsch